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A wire can just support a load of 20 kg before it breaks. If this wire is cut into two equal halves, what maximum load can each half support?

1. 10 kg
2. 20 kg
3. 40 kg
4. 80 kg

Correct answer: 20 kg

Solution

Maximum load = breaking stress x area, independent of length; each half has the same cross-section, so it still supports 20 kg.

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